in our fact or fiction segment, we look at a claim and ad by president obama about abortion. the ad claims that mitt romney and paul ryan are both "opposed to abortion even in cases of rain and incest." while that is true of ryan's positionment position. it is not necessarily true of romney. he says he allows for exceptions of rain and incest and if the mother's life is at risk. the obama campaign says romney supported the republican party platform that would ban abortion without exception is their claim is valid. >>> we have new information on the search for the cause of the deadly hasn't virus outbreak at yosemite. scientists looking in to the matter say a spike in the deer mouse population combined with the design of the cabins would be to blame. they were built in a way that mice could easily nest in the insulation. tiny particles can float in the air and humans can breathe it in. and another theory of a mutation in the virus is unlikely. nine people who spent time at the park over the summer became infected and three of them died. >>> there's a possible breakthrough in b